document.write( "Question 133506: Subtract and simplify completely:\r
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Algebra.Com's Answer #97681 by solver91311(24713) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"%28%284y%5E2-x%5E2%29%2F%28x-y%29%29-%28%28-3y%5E2%29%2F%28y-x%29%29\"$ \r
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\n" ); document.write( "\n" ); document.write( "The trick on this one is to note that $\"x-y=-1%28y-x%29\"$ , so you can write:\r
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\n" ); document.write( "\n" ); document.write( " $\"%28%284y%5E2-x%5E2%29%2F%28x-y%29%29-%28%283y%5E2%29%2F%28x-y%29%29\"$ \r
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\n" ); document.write( "\n" ); document.write( "Now that you have the same denominator in both fractions, you can simply add the numerators:\r
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\n" ); document.write( "\n" ); document.write( " $\"%28%284y%5E2-x%5E2%29-%283y%5E2%29%29%2F%28x-y%29\"$ \r
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\n" ); document.write( "\n" ); document.write( "Now combine like terms:
\n" ); document.write( " $\"%28y%5E2-x%5E2%29%2F%28x-y%29\"$ \r
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\n" ); document.write( "\n" ); document.write( "Now you have the difference of two squares in your numerator, so factor it:\r
\n" ); document.write( "\n" ); document.write( " $\"%28%28y-x%29%28y%2Bx%29%29%2F%28x-y%29\"$ \r
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\n" ); document.write( "\n" ); document.write( "Again note that $\"x-y=-1%28y-x%29\"$ , so $\"%28y-x%29%2F%28x-y%29=-1\"$ , and now you can write:\r
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\n" ); document.write( "\n" ); document.write( " $\"%28%28y-x%29%28y%2Bx%29%29%2F%28x-y%29=-%28y%2Bx%29\"$ or $\"-y-x\"$ if you prefer. \n" ); document.write( "

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